Abstract: Microlaminated composite articles are made by combining one or more sheets of flexible sintered crystalline ceramic foil with one or multiple inorganic substrate layers, e.g., of metal foil, to form a stack which is then heated below the melting temperatures of the foil and substrate layers, and under slight or moderate pressure, to provide a well-bonded composite article which is essentially free of interlaminar cementing or sealing materials.

Abstract: Composite articles sintered polycrystalline ceramic reinforcing members in a co-sintered, inorganic, preferably ceramic matrix, formed by disposing arrays of green reinforcement precursor structures in a matrix preform and then consolidating the preform by compacting, debindering, and pressureless sintering, the resulting co-sintered composites exhibiting zero open porosity, high density, and improved work-of-fracture characteristics, are described.

Abstract: Thermal-shock-resistant fuel cell designs comprising flat and corrugated ceramic sheets combined to form channeled structures, the sheets being provided as thin, flexible ceramics and being particularly effective when used as components of compliant electrolyte substructures incorporating the flexible ceramics with fuel cell electrodes and/or current conductors bonded thereto, are described.

Abstract: Non-spherical bodies having a circular cross-section that is 0.5-200 microns in diameter and that are longer than the cross-sectional diameter, and a method of making such bodies by reshaping non-spherical bodies. The method comprises positioning a monolayer of unsintered, deformable, spherical bodies between smooth facing surfaces on two flat formers, and applying a mild shearing force to at least one of the formers.

Abstract: Hard crystalline sintered ceramic products, and a method for making them at substantially reduced sintering temperatures, are disclosed, the products being manufactured by the sintering of mixtures comprising one or more ceramic powders selected from among zirconia, stabilized zirconia, partially stabilized zirconia, alumina, mullite, cordierite, and MgAl.sub.2 O.sub.4 spinal together with a combination sintering aide including TiO.sub.2 and at least one transition metal oxide selected from the group consisting of copper oxide, manganese oxide, cobalt oxide and zinc oxide, the mixture comprising at least about 3.5 mole percent TiO.sub.2, at least about 1.3 percent of transition metal oxides, about 4.8-50 mole percent total of TiO.sub.2 +transition metal oxides, and the remainder ceramic powder. Sintering of these mixtures at temperatures typically 200.degree.-350.degree. C.

Abstract: Thin inorganic sintered structures having strength and flexibility sufficient to permit bending without breakage in at least one direction to a radius of curvature of less than 20 centimeters, methods for making them, and products incorporating them, are described. Preferred sintered ceramic structures according to the invention can comprise zirconias, titanias, aluminas, silicas, rare earth metal oxides, alkaline oxides, alkaline earth metal oxides and first, second, and third transition series metal oxides and combinations thereof and therebetween. Sintered metal structures can also be provided.

Abstract: Two composition areas of partially stabilized ZrO.sub.2 /HfO.sub.2 alloys have been discovered which exhibit pseudo-plasticity through the presence of transformation bands and with the substantial absence of microcracking. The first area consists essentially, in mole percent, of 0.5-8% of at least one toughening agent in the indicated proportion selected from the group consisting of 0-8% YNbO.sub.4, 0-8% YTaO.sub.4, 0-8% RENbO.sub.4, 0-8% RETaO.sub.4, 0-8% YVO.sub.4, 0-8% REVO.sub.4, 0-8% MgWO.sub.4, 0-8% MgMoO.sub.4, 0-8% CaWO.sub.4, 0-8& CaMoO.sub.4, and 0-8% SnO.sub.2, and 0.5-10% of at least one stabilizer oxide in the indicates proportion selected from the group consisting of 0-3.5% Y.sub.2 O.sub.3, 0-3.5% Sc.sub.2 O.sub.3, 0-3.5% RE.sub.2 O.sub.3, 0-10% CeO.sub.2, 0-10% TiO.sub.2, 0-10% SnO.sub.2, 0-10% CaO, and 0-10% MgO, with the remainder ZrO.sub.2 /HfO.sub.2 alloy. The second area consists essentially, in mole percent, of 8-16% CeO.sub.2 and 0.25-5% Nb.sub.2 O.sub.5 and/or Ta.sub.2 O.sub.

Abstract: This invention is directed to the production of ceramic alloys consisting essentially of partially stabilized ZrO.sub.2 and/or ZrO.sub.2 -HfO.sub.2 solid solution and/or HfO.sub.2 exhibiting high toughness through the inclusion of about 0.5-8 mole %, as expressed on the oxide basis, of YNbO.sub.4 and/or YTaO.sub.4 and/or MNbO.sub.4 and/or MTaO.sub.4, wherein M represents Mg.sup.+2, Ca.sup.+2, Sc.sup.+3 and/or a rare earth metal ion selected from the group of La.sup.+3, Ce.sup.+4, Ce.sup.+3, Pr.sup.+3, Nd.sup.+3, Sm.sup.+3, Eu.sup.+3, Gd.sup.+3, Tb.sup.+3, Dy.sup.+3, Ho.sup.+3, Er.sup.+3, Tm.sup.+3, Yb.sup.+3, and Lu.sup.+3 substituted for Y, and the use of at least 5 volume percent of such ceramic alloys to toughen hard refractory ceramics.

Abstract: This invention is primarily directed to the production of transformation toughened ZrO.sub.2 -containing ceramic alloys wherein the toughening agent is selected from the group consisting of a rare earth metal vanadate and a magnesium and/or calcium tungstate/molybdate, and SnO.sub.2 can be utilized as a toughening agent and/or a stabilizing agent for ZrO.sub.2.

Abstract: An apparatus and process for producing liquid droplets having a narrow size distribution. Thin liquid streams are forced under pressure through a plurality of orifices in an orifice plate, the largest of which orifices has a diameter not greater than about three times the diameter of the smallest of those orifices. Also the thin liquid streams are vibrated to cause the breakup of each stream into droplets having a narrow size distribution.

Abstract: Whisker-toughened ZrO.sub.2 products containing 5-20 volume percent SiC whiskers of relatively low aspect ratio (<20) in a stabilized polycrystalline ZrO.sub.2 matrix are provided, exhibiting a room temperature fracture toughness (K.sub.IC) at least 1.25 times that of the ZrO.sub.2 matrix, with relatively low porosity and good strength.

Abstract: This invention is concerned with the production of a hard, tough, thermally conductive ceramic cutting tool insert consisting essentially of a zirconia alloy in a hard refractory ceramic insert. The ceramic cutting tool insert exhibits performance conducive to use in turning operations and/or milling operations.

Abstract: This invention is directed to the production of ceramic alloys consisting essentially of ZrO.sub.2, titania, and yttria or rare earth oxides such as gadolinia, ytterbia, neodymia, and ceria. Mole % concentration values as low as 0.25 mole % for yttria have been found to provide a hard and tough ceramic alloy in the presence of the titania-zirconia body. These compositions have been found to produce effective hard and tough ceramic bodies when mixed with refractory fibers and/or whiskers and hard refractory ceramics.